how to implement strong antispam

Hi All

I need to implement strong antispam because I have in the INBOX on users spam mail.
Other problems is the spam that is detected is stored in the Junk Mail folder, how can I to configure for that the spam mail not stay in any folder, I want that all spam deleted.

Spam does not stay in the Junk folder eprmanently, it's gets deleted after a period of time that you set in the Admin UI. Perhaps you ought to find out why you have spam in the users Inbox, search the forums for some tips as it's been covered before.

You might also want to post details of what you version of Zimbra is, what sort of spam is in the Inbox (post some headers), what your Kill/Tag percentages are etc...

The downside with the wiki solution for better antispam is much of it is eliminated when there is a Zimbra upgrade. We need to find a way which is a bit more durable when upgrading and would be better to build into Zimbra for configuration and whatnot.

I know this isn't the answer people are looking for, but I implemented a set of rules on our firewall to block countries that my users shouldn't have any business talking to. I did this more for content filtering but I noticed our spam decreased drastically when I did that. I am talking we went from probly around 1,000 spam a day to about 20. The downside is sometimes your users do have a legit reason to talk to IPs in these countries so you have to unblock them one at a time, but imo it was worth it. I use zen.spamhaus.org as an rbl, which helps filter the U.S. spam we get. I work for a school district though here in the U.S. so 90% of our emails we get are from parents here in our town or other school districts here in our state. I know businesses email people in other countries all the time, so you have to think about it a lot before you would do something like this. Between the firewall rules, spamhaus, and the anti-spam system zimbra has, we don't have any problem at all with spam as of now (knock on wood). We get a few here and there, but it isn't a problem. Our users realize that spammers dedicate much more time getting spam into our inboxes than I have to keep them out, so one every now and then isn't too shabby.

I use a combination of multiple RBLs, lowered tag & kill percentages (as OP has already done), modified scores for places that IMHO SpamAssassin is too tolerant, and penalty-scoring all commercial whitelists. I keep all such modifications in a single file /opt/zimbra/conf/spamassassin/local.cf and I keep that file backed up. That way, when I do an upgrade it's a simple matter of copying local.cf from my backup into the live directory, stop & restart spamassassin and everything stays up.

YMMV, but I've found the following Bayes modifications in local.cf to make my SA scores a lot more effective:

The bottom line is, once you have some basic settings in your system, you need to take a look at the headers of messages that are still coming through. See what is going on in those headers, that isn't properly being scored by your system. If you like, post a couple headers here and we'll look at them with you. Often it only takes a couple tweaks to the scoring to solve fairly significant spam problems...and once solved, I find it to be pretty much set-and-forget.